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<b>DB-&gt;sync</b>
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<b><pre>
#include &lt;db.h&gt;
<p>
int
DB-&gt;sync(DB *db, u_int32_t flags);
</pre></b>
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<b>Description: DB-&gt;sync</b>
<p>The DB-&gt;sync method flushes any cached information to disk.</p>
<p>If the database is in memory only, the DB-&gt;sync method has no effect and
will always succeed.</p>
<p><b>It is important to understand that flushing cached information to disk
only minimizes the window of opportunity for corrupted data.</b> Although
unlikely, it is possible for database corruption to happen if a system
or application crash occurs while writing data to the database.  To
ensure that database corruption never occurs, applications must either:
use transactions and logging with automatic recovery; use logging and
application-specific recovery; or edit a copy of the database, and once
all applications using the database have successfully called
<a href="../api_c/db_close.html">DB-&gt;close</a>, atomically replace the original database with the
updated copy.</p>
<p>The DB-&gt;sync method
returns a non-zero error value on failure
and 0 on success.
</p>
<b>Parameters</b> <br>
 <b>flags</b><ul compact><li>The <b>flags</b> parameter is currently unused, and must be set to 0.</ul>
<br>
<br><b>Errors</b>
<p>The DB-&gt;sync method
may fail and return one of the following non-zero errors:</p>
<br>
<b>DB_REP_HANDLE_DEAD</b><ul compact><li>The database handle has been invalidated because a replication election
unrolled a committed transaction.</ul>
<br>
<br>
<b>DB_REP_LOCKOUT</b><ul compact><li>The operation was blocked by client/master synchronization.</ul>
<br>
<br>
<b>EINVAL</b><ul compact><li>An
invalid flag value or parameter was specified.</ul>
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<br><b>Class</b>
<a href="../api_c/db_class.html">DB</a>
<br><b>See Also</b>
<a href="../api_c/db_list.html">Databases and Related Methods</a>
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